1. Field of the Invention
The invention relates to a warp thread tensioning apparatus used in a weaving machine and comprises a rotatably supported carrier beam acting a distance from its axis of rotation on a warp thread-tensioning device and loaded preferably with a prestressed torsion spring.
2. Description of the Related Art
Apparatus of the above kind is known from U.S. Pat. No. 4,534,386. This patent discloses that the warp tension can be determined by the angular position of the carrier beam and optionally may be used to regulate or control the warp thread letting off speed. In this patent, the angular position of the carrier beam is determined not only by the warp tension, thus the determination of warp tension is fairly inaccurate.
It is known from U.S. Pat. No. 5,029,619 to determine the warp tension from the force that is exerted by parts of the warp threads via a sensor. The measured force depends on the number of warp thread threads acting on the sensor. Therefore care must be made that the number of warp threads remain constant. Moreover this design includes the danger of the sensor damaging the warp threads.